Criteria to assess
Case study 2: HFPO-DA
Serious effects to human health
Poses a threat to human health?
There is evidence that the general population can be exposed to HFPO-DA via several routes including drinking water, locally emitted air, home grown fruits and vegetables, plants and fish. Removal from water is very difficult and current methods are likely insufficient to achieve removal. Observed effects in rodents' liver, kidney, haematological system, immune system and related to development can be a cause of concern for humans. Due to the positive response in a rodent carcinogenicity study (i.e., pancreatic-, liver- and testis tumours), HFPO-DA could be a possible human carcinogen
Irreversible health effects?
HFPO-DA adversely impacts human health at a daily intake that could be as low as 21 ng/kg bw/day (tTDI). HFPO-DA has been found in the serum of residents living close to a fluorochemical plant in China, and in the blood of employees from a fluorochemical production plant in the Netherlands
Delayed health effects?
The effect on human health may come with a possible delay between exposure and the onset of any observable adverse effect (i.e., cancer). In addition, health effects may also be relevant for short-term exposure (i.e., immune effects, haematological effects, liver effects, kidney effects)
Impaired quality of life?
The evidence above shows that there are serious health effects that can be felt based on already released HFPO-DA and future emissions. Water sources will be compromised, pollution must be remediated, and both affect quality of life
Serious effects to the environment
The high persistence and chronic background concentrations of HFPO-DA implies that there is a continuous and irreversible exposure once chemicals are released in sufficient quantities to aquatic resources. Exposures are not expected to decrease upon cessation of releases because of the high persistence of the substance. Current lack of water treatment methods results in irreversible exposure
The very persistent and very mobile nature of HFPO-DA means that a cessation of emissions will not necessarily result in a reduction in concentration. Observed adverse effects on humans and current information on toxicity shows that effects can be considered irreversible. Chronic background concentrations result in continuous exposure that may also lead to the irreversibility of adverse effects
Intergenerational exposure and effect?
Cessation of emissions will not necessarily result in a reduction in substance concentration and continuous exposure over very long times can lead to inter-generational effects that will impact the quality of life and are of high societal concern. Due to the high persistence and lack of biodegradation, exposure in aquatic media will remain over multiple generations. As such, effects of current emissions may be observed or only become apparent in next generations
Unknown/uncertain spatial scale?
The high persistency and the high mobility of HFPO-DA lead to long distance transport processes in the environment. HFPO-DA has been reported to have been transported over a distance of at least 1700 km after its emission from the Rhine Meuse delta into the North Sea. The high mobility in the aqueous environment means it can spread to other environmental compartments rapidly and is transported by sea currents and via air. Observed concentrations in disconnected water bodies, soil and ground water are linked to subsequent wet and dry deposition of HFPO-DA after emission to air
Disparity between point of release and point of effect?
Due to the potential for wide spread distribution and long-range transport of HFPO-DA, effects will not only occur at the point of release but also far away from its point of release
Unknown/uncertain temporal scale?
There is a current lack of information and thus uncertainty related to the temporal scale of effects of HFPO-DA based on its more recent introduction to the market
Uncertain/difficult to predict long term fate and toxic effects?
The very high persistency of the substance and the current uncertainties in bioaccumulation make long term fate and toxic effects difficult to predict and widely unknown
Harmful to the aquatic environment?
HFPO-DA has been observed in multiple water bodies around the world as it is highly mobile and spreads with water. It has been detected in surface water, raw water and drinking water. HFPO-DA has been observed in fish from China, the USA and the Netherlands. The co-exposure of HFPO-DA with other contaminants including other very persistent fluorochemicals such as PFOA, perfluorohexanoic acid (PFHxA) and PFBS present in the environment lead to possible combination effects. The demonstrated effects on humans and biota, combined with the compromised effect on water, render HFPO-DA harmful to the aquatic environment
Potential to reach remote pristine areas?
The potential for long range transport modelled using the Long-Range Transport Tool resulted in a characteristic travel distance of 8682 km. This indicates that HFPO-DA can reach any area in the world before any significant amount of substance degradation has occurred. Current fate modelling suggests the water compartment to be the main residence compartment
Increased societal costs?
The continuous long-term exposure of humans can impact quality of life and is of high societal concern. Irreversible concentrations in the environment will, furthermore, lead to inter-generational effects. Intrinsic chemical properties mean that there is a lack of drinking water treatment methods able to remove HFPO-DA which must be developed and paid for by society
Negative effect on resources?
There are few methods that can be used to treat water on the larger scale. This presents a negative effect on resources. No significant removal capacity was demonstrated in the different steps of the drinking water treatment process in a drinking water treatment plant. Water was sampled after each step in the purification process (raw water, ozonation, coagulation/flocculation/sedimentation, settled water ozonation, biological activated carbon filtration, and disinfection by medium-pressure UV lamps and free chlorine)
Do emissions need to be minimized?
The intrinsic properties mean that emission reduction mitigation measures are needed and current spreading and toxic effects on affected populations may be difficult to reverse